ECAT Pre General Science MCQ Test With Answer for Mathematics Chapter 9

A die is thrown 100 times. If getting an odd number is considered a success, the variance of the number of successes is

• 50 A
• 25 B
• 10 C
• 100 D

• 
  A
• 
  B
• 
  C
• 
  D

nCn-r is equal to

• n! A
• n-1Cr B
• nCr C
• None of these D

• P(A) + P(B) A
• P(A) - P(B) B
• P(A) . P(B) C
• P(A) / P(B) D

• 0.9 A
• 0.74 B
• 0.2016 C
• None of these D

• 3 A
• 6 B
• 0 C
• None of these D

(n + 2) (n + 1)n in factorial form is

• 
  A
• 
  B
• 
  C
• 
  D

• 120 A
• 5 B
• 4 C
• 6 D

If two balls are drawn from a bag containing 3 white, 4 black and 5 red balls. Then the probability that the drawn balls are of different colours is

• 1 / 66 A
• 3 / 66 B
• 19 / 66 C
• 47 / 66 D

A box containing 10 mangoes out of which 4 are rotter. Two mangoes are taken together from the box. If one of them is found to be good, the probability that the other is also good is

• 1 / 3 A
• 8 / 15 B
• 5 / 13 C
• 5 / 9 D

If A is an event then which of the following is true

• P(A)<0 A
• 0≥P(A)≤1 B
• P(A)>0 C
• None D

For two events A and B if P(A) = P (A/B) = 1/4 and P(B/A) = 1/2, then

• A is sub-event of B A
• A and B are mutually exclusive B
• A and B are independent and P(A/B) = 3/4 C
• None of these D

6! = ______

• 360 A
• 720 B
• 6.5.4 C
• None of these D

• 0 A
• 20 B
• 90 C
• 80 D

The sum of all even numbers less than 100 is

• 2450 A
• 2352 B
• 2272 C
• 2468 D

A committee consists of 9 experts taken from three institutions A, B, and C, of which 2 are from, A, 3 form B and 4 from C. If three experts resign, then the probability that they belong to different institutions is

• 1 / 729 A
• 1 / 24 B
• 1 / 21 C
• 2 / 7 D

• 
  A
• 
  B
• 
  C
• 
  D

A key ring is an example of

• Permutation A
• Circular permutation B
• Combination C
• None D

A sequence is a function whose domain is

• N A
• Subset of N B
• R C
• None of these D

• 110 A
• 220 B
• 1320 C
• None of these D

If S is a sample space and event set E = S then P(E) is

• >0 A
• 1 B
• <1 C
• 0 D

When a selection of object is made without paying regard to the order of selection, it is called

• Sequence A
• Series B
• Combination C
• Permutation D

An integer is chosen at random from the number ranging from 1 to 50. the probability that the integer chosen is a multiple of 2 or 3 or 10 is

• 3 / 10 A
• 5 / 10 B
• 7 / 10 C
• 9 / 10 D

probability of a certain event is

• 0 A
• -1 B
• 1 C
• ∞ D

Five engineering, four mathematics, two chemistry books are placed on a table at random.The probability that the books of each kind are all together is

• 
  A
• 
  B
• 
  C
• 
  D

How many arrangements of the letters of the word MATHEMATICS can be made

• 
  A
• 
  B
• 
  C
• 
  D

• 5 / 12 A
• 3 / 8 B
• 5 / 8 C
• 7 / 4 D

20. 19. 18. 17= _______

• 
  A
• 
  B
• 
  C
• 
  D

For a positive integer n

• n! = n(n + 1) A
• n! = n(n+1)! B
• n! = n(n - 1 ) C
• n! = n(n - 1)! D

• n! A
• 0! B
• 1 C
• None of these D